I wrote this on page 65, the only change is that Maldonado is confirmed for Lotus next year & rosberg has extended his contract too:
There aren't many top drivers available for next year:
Vettel - contracted to RBR until end of 2015
Ricciardo - contracted to RBR until end of 2015
Hamilton- contracted to Mercedes until end of 2015
Rosberg - contracted to Mercedes until end of 2016
Alonso - contracted to Ferrari until end of 2016
Raikkonen - contracted to Ferrari until end of 2015
Massa- contracted to Williams until end of 2016
I can't find details on Bottas's availability. Perez has already been dropped and they've discounted Hulkenberg. JEV hasn't shone against KVyat who does not have the experience. Sutil's ship has sailed & I doubt Estaban is even on their radar. That leaves Grosjean, Maldonado, Kobyashi, Bianchi, Chilton & Ericsson or recruit from GP2 - which jars against their experience requirement.
Or they could stick with Button & Magnussen for 2015.
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I still can't find info on Bottas, but it's worth noting that his manager is Toto Wolff. TJ13 speculated that VB could replace Hamilton at Mercedes but then TJ13 never miss an opportunity to write something negative about LH. I do wonder though if Wolff will want to keep Bottas at Williams as a 'plan B' incase LH leaves Mercedes at the end of 2015- either way I don't think Bottas will replace JB at Mclaren. I think the 2nd seat is a straight fight between JB and Grosjean.